COMMUNICABLE DISEASES. 207 



to better qualify the pharmacist to cooperate with the health officers in 

 safeguarding the public health. 



A. Tuberculosis. Commonly known as consumption and the " white 

 plague." A universal disease, essentially infectious, especially peculiar to 

 crowded habitations and to lack of pure fresh air. The primary cause is 

 the Bacillus tuberculosis (bacillus of Koch), a non-spore-bearing microbe, 

 which is somewhat more resisting to disinfectants and other destructive 

 agencies than most other pathogenic bacteria. The chief predisposing 

 causes are living in crowded habitations; inherited low vitality, especially 

 weak lungs; and exposure to inclement weather. The disease may be 

 general (general tubercular infection) or it may be localized in any one or in 

 several organs or tissues. Commonly localized in the lungs (phthisis, con- 

 sumption) and in lymph glands. Lupus and many so-called scrofulous 

 conditions are tuberculosis of the skin; the disease often attacks bones and 



f -. 



IN 



FIG. 81. Bacillus tuberculosis. Although this organism does not form spores it is 

 quite resistant to the action of germicides. The bacillus causing the bovine type of tuber- 

 culosis differs slightly in several characteristics from the bacillus of human tuberculosis. 



joints (hip-joint disease of children). It attacks young and old and may 

 occur in all walks of life. The disease enters via the air passages and per 

 mouth with food and drink, or through cuts, bruises, wounds and abrasions. 

 It is contracted by inhalation through close association with consumptives, 

 and the bovine form or type of tuberculosis is acquired from the milk of 

 tubercular cows. Bovine tuberculosis is especially liable to affect the lymph 

 glands and the joints. 



The disease sometimes runs a quick course (quick consumption), but 

 more generally it makes an insidious start and runs a chronic course. Many 

 people have limited local infections which are only discovered at an autopsy. 

 There are many spontaneous recoveries from tuberculosis. Since it is 

 very important to begin early treatment, the physician resorts to several 

 tests for the purpose of determining the possible existence of masked or 

 incipient forms of the disease. These tests are as follows and all depend 



